Accumulator fuel injection system



Patented June 10,194!

- gumm STATE SPATENT OFFICE ACCUMULATOR FUEL INJECTION SYSTEM I Donald E. Meitzler, Manchester, Comm, assignor to United Aircraft Corporation, .Conn., a corporation of Delaware East Hartford,

- e Application July 2:, 1943, Serial No. 495,928

5 Claims. (Cl. 103-41)" This invention relates toaccumulator iniection apparatus. 7 i

For airless injection of fuel thesaccumulator chamber of apparatus of this type must be free by a spring 44.

controlled by a check valve 40 held against a seat When accumulator valve 24 moves to open passage 32, fuel pressure opens. the

check valve 40 and fuel discharges past the check valve until the'pressure of spring 44 is greater than the pressure differential holding the valve open. The checkgvalve may have an integral plunger 4B s1ideablej1n 'a "bore 48 in nozzle 34, the

Air in the accumulator chambers l8 and is plunger having a longitudinal groove 60 for flow of fuel past the plunger; Nozzle 34 has one or more openings 52 for discharge of fuel.-

vented through a passage 54 in casing 10 which accumulator chamber regardless of the position i of the chamber. i

Another feature of this invention is an accumulator injection apparatus which may be installed in any position without afiecting the proper g venting of the accumulator chamber. Another feature is an arrangement of several spaced ports in the accumulator chamber so that p at leastone of theports will be substantially at the top of the chamber regardless of the position of the chamber,

Other objects and advantages will be apparent from the specification and claims, andfrom theaccompanying drawing which illustrates anjembodiment of the invention.

Fig. 1 is a sectional view through-the injection, apparatus.

Fig. 2 is a fragmentary sectional view showing the plunger at the other end of its stroke? The casing It has a bore l! in which isja plunger l4. With the plunger in the position shown in Fig. 2 before it begins its injection stroke, an inlet port i6 admits fuel to the end of the bore l2. Duringthe injection stroke fuel is forced by the plunger l4 into accumulator chambers I8 and 20 through a groove 22 in a valve 24' and cross-passage 26. This valve is slideable in a bore 28in a ring 30 in the casing.v

, While fuel is being forced into the accumulator connects with the chambers. The opposite end of passage 54 forms a port 56 in bore l2 opposite a relief port 58 which-may be connected to a drain. Plunger l4 has a groove 60 which during the plunger strokeconnects ports 58 and -58 so that any air in the accumulator chambers charged through the passage (see Fig. 2)

Each accumulator chamber is substantially cylindrical and the opposite ends oi. each chamber are provided with a series of. ports 62 and 64' which connect with passage. The ports of each series are uniformly spaced about the pe-" ripheryof the cylinder wallso that one ofthe ports will be at the high point ofthe' chamber in substantially any position of the cylinder. A

ring 66 having a conical inner surface may be positioned in the inner end of each cylindrical chamber, and the ports 64 are formed as grooves in the outer surface of this ring. All of these ports connect with an annular groove 10 in the periphery of the ring with which passage 54 communicates. Ports 62 may be formedin a plug 12 defining theouter end of the chamber, and these chambers, valve 24 closes a passage 32 which connectspassage 2G with the. discharge nozzle 34. One end of valve 24 is in line with a seat 36 at the end of passage Band is held on this'seat by pressure of fuel on the other end of the valve during the injection stroke of the plunger.

Groove 22 extends longitudinally of valve 24 to permit a throttled flow of fuel past the valve into the accumulator chamber. The end of valve 24 remote from seat 36 is conical to engage a seat 38 at the end of bore 28 communicating with bore l2,

and to close the end of groove 22.

Discharge of fuel through passage 32 may be ports all communicate with an annulargroove '4 connecting with passage 54, r

By the arrangement of the series of ports 82 and 64 as shown, the injection apparatus may be placed in any position without affectin the:

proper venting of the chambers, since, as above stated; one of the ports willbe at substantially the high point of the chamber-in almost any position of the apparatus.

During the pumping stroke of the plunger, the head of the plunger closes inlet port It and port 56 is closed by the edge of groove 60. As the.

I plunger continues its pumping stroke with these portsfclosed, fuei'is accumulated under pressure in the chambers until port It is uncovered by groove 80. when this occurs, fuel from the space at the head of the plunger discharges through a passage It extending from the head of the plunger to groove 60. The resulting reduction in pressure in theplunger bore causes valve 24 to move endwise, opening passage 32 for the discharge of fuel from the accumulator chambers through the nozzle. As the conical valve surface now en- Sages valve seat 38, flow of fuel through groove 22 is prevented. Accumulator valve '14 is again moved to engage seat 36 when theplunger begins its next pumping stroke.

During thereturn stroke of pump plunger i4,

groove 60 connects ports .66 to I8 and the prese sure remaining in'chambers if and 29 forces out through passage 64 any air that may bein these chambers. Thus during each stroke of the pump plunger, the accumulator chambers. are vented to prevent the accumulation of'gas or air bubbles.

It is to be understood that the invention is not limited to the specific embodiment herein illustrated and described, but maybe used in other 7 ways without departure from its spirit as defined by the following claims. r Iclaim:-

1. Injection apparatus comprising a pump, an accumulator chamber in which fuel is accumulated by said, pump, and means for venting said chamber in any position of the chamber to remove gas bubbles collecting therein; said means includa ing several ports in the chamber so arranged that 4 substantially cylindrical accumulator chamber in which fuel is accumulated by said pump, and

means for venting said chamber in any position of the chamber to remove gas bubbles collecting therein, said means including several spaced ports at each end of the chamber, so arranged that a port will be substantially at the high point of the chamber in any position of the chamber, and

. a connection between said ports and a vent.

5. Injection apparatus comprising a movable pump plunger, a casing having a bore for said plunger, an accumulator chamber in which fuel is compressed by said plunger, means for venting said chamber for removing gas collecting therein including several spaced ports in the chamber so arranged that a port will be substantially at the high point of the chamber in any position of the chamber, a connection from said ports to a port in the plunger bore, and means on the plunger for connecting the port in the bore to a vent 1 during a part only of the plunger stroke."

6. Injection apparatus 'comprising'a movable .pump plunger, a casing having a bore for said I plunger, an'ac'cumulator chamber in which fuel at least one of the ports will be at the high point of the chamber in substantially any position of a the chamber.

2. Injection apparatus comprising a pump, a substantially cylindrical accumulator chamber in which fuel is accumulated by said-pump, and means .or venting said chamber in any position of the chamber to remove gas bubbles collecting therein, said means including several spaced ports located around the peripheries of the end walls at each end of the chamber so arranged that a port will be substantially at the high point .of the chamber in any position of the chamber.

is compressed'by said plunger, means for venting said chamber for removing gas collecting therein including several spaced ports in the chamber .arrangedthat a port will be substantially at the high pointof the chamber in any position of the chamber, a groove in said plunger, opposed ports in the bore adapted to be connected by the plunger, one of said ports being a vent and the other port being connected to the ports in the accumulator chamber. r

E. MEITZLER.

REFERENCES crrsn,

'1'he following references are of record in the die of this patent:

mn'mn s'rs'ms Pam-rs Number Name I i Date 1,883,980 Lang Oct. 25, 1932 1,596,194 Lang Aug. 17, 1928 2,131,779 Zwick et al. Oct. 4. 1938 1,473,761 Grant Nov. 13, 1923 1,604,492 Smith Oct. 26, 1926 1,653,885 Van Guilder L. Dec. 27, 1927 1,802,933 Von Sails Apr. 28, 1931 Steiner Dec. 13, 1932 

